Parliament Hill was briefly locked down Thursday morning after RCMP officers discovered explosives in a pickup truck during a routine vehicle inspection.

It turned out the explosives had been accidentally left inside a construction vehicle.

Parliament Hill and the House of Commons were immediately closed and RCMP and security officers quickly went into high alert.

"They discovered a pickup truck that was carrying explosives of the C4 variety. It turned out this apparently was a contractor who was working on Parliament Hill," reported CTV’s Ottawa Bureau Chief Robert Fife.

After investigating, security officials determined the contractor was simply trying to get to work. It isn't clear why he was carrying the explosives.